That was my first thought when I looked at it. Most of the variegated leaves are on one half of a y and most of the green leaves are on the other half of the y. That seemed like a simple answer. However when I looked closer there are some twigs that are mixed. So I'm not sure that is the case. I don't assume they can share genetics back and forth between the two halves of the y right?Is it possible that the tree is grafted and the original plant has popped up a shoot that's now competing with the grafted scion?
Agreed. They revert at the drop of a hat. Once it starts reverting it’s nearly impossible to control. I’d just start pruning out the variegated sectionsIt's variegated. some of the Japanese Maple variegated cultivars start to revert over time.
We see that a ton out here in the PNW, with so many stupid J. Maple cultivars. Its like the tree decides it is fed up with not photosynthesizing enough.